Seawater batteries of the type having a magnesium or magnesium alloy anode and a lead chloride cathode are conventionally separated by polymer spacers from adjacent electrodes of opposite polarity but are connected to each other through the intercell partition, which may typically be a thin film of electrolyte resistant polymer, by a metal connector. This metal connector passes through the metal conducting support of the cathode and is in electrical contact therewith and with the anode. In order to prevent corrosion problems at this metal connector, which typically may be a staple, it is necessary for the active material of the cathode to be removed around the connecting location so that a window is formed in the cathode in which the staple can be located in a position such that it does not contact the active material.